Water resource accounting for an iron-ore mining area in India

Abstract

A study has been conducted at the Bicholim iron-ore mine, North Goa, India to investigate the hydrogeological continuity between the mine's open pit and surrounding villages. Water resource accounting by demarcating different watersheds has also been carried out to analyse the major causes of groundwater scarcity in the region during dry periods. A resistivity survey and a ground penetrating radar survey were completed around the periphery of open pits, the surrounding village areas and Mayem Lake. The results of the two independent surveys and other related data confirm that there is no observable hydrogeological continuity between the pits, nearby villages and Mayem Lake. Hence, there may not be any significant effect on surrounding water resources due to mining or mine dewatering. Water resource accounting has revealed that only 15–20% of 3500 mm precipitation per annum becomes part of the groundwater resource. The remainder of the annual precipitation is lost as heavy runoff, evapotranspiration and subsurface capillary moisture. Closely spaced wells in the region have also aggravated the groundwater scarcity problem due to draw down effects. Therefore, an effective water resource conservation plan is required for the region to overcome the problem.